Re: [PATCH v2 1/8] PCI/AER: Remove aer_print_port_info

[Bjorn Helgaas <helgaas@kernel.org>]

On Thu, Feb 13, 2025 at 06:35:36PM -0800, Jon Pan-Doh wrote:
> Info logged is duplicated when the source device is processed. In both
> cases, BDF and error severity are derived from aer_error_info. If
> no source device is found, then an error is logged with the BDF from
> aer_error_info.

Nit: say what the patch does in the commit log as well as in the
subject.

> Code flow:
> aer_isr_one_error()
> -> aer_print_port_info()
> -> find_source_device()
>    -> return/pci_info() if no device found else continue
> -> aer_process_err_devices()
>    -> aer_print_error()

Nit: drop "->"; the indentation is enough.

> aer_print_port_info():
> pcieport 0000:00:04.0: Correctable error message received
> from 0000:01:00.0

Nit: don't wrap log messages, and indent them a couple space since
they're quoted material.

> aer_print_error():
> e1000e 0000:01:00.0: PCIe Bus Error: severity=Correctable, type=Data Link Layer, (Receiver ID)
> e1000e 0000:01:00.0:   device [8086:10d3] error status/mask=00000040/0000e000
> e1000e 0000:01:00.0:    [ 6] BadTLP

Give us a clear sample of the log showing the duplicated info.  Are
you're referring to this:

  pcieport 0000:00:04.0: Correctable error message received from 0000:01:00.0
  e1000e 0000:01:00.0: PCIe Bus Error: severity=Correctable, type=Data Link Layer, (Receiver ID)
  e1000e 0000:01:00.0:   device [8086:10d3] error status/mask=00000040/0000e000
  e1000e 0000:01:00.0:    [ 6] BadTLP

where the pcieport message refers to 0000:01:00.0, and the subsequent
e1000e messages also include 0000:01:00.0?

It's true this is redundant information, but that e1000e device may
no longer be accessible.

In that case, I think aer_get_device_error_info() would probably
return 0 because config reads would all return ~0, and
PCI_ERR_COR_STATUS & ~PCI_ERR_COR_MASK would be 0, so
we probably wouldn't see the e1000e messages at all.

> Tested using aer-inject[1]. No more root port log on dmesg.
> 
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/gong.chen/aer-inject.git
> 
> Signed-off-by: Jon Pan-Doh <pandoh@google.com>
> Reviewed-by: Karolina Stolarek <karolina.stolarek@oracle.com>
> ---
>  drivers/pci/pcie/aer.c | 15 ---------------
>  1 file changed, 15 deletions(-)
> 
> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
> index ad4206125b86..9a8cc81d01e4 100644
> --- a/drivers/pci/pcie/aer.c
> +++ b/drivers/pci/pcie/aer.c
> @@ -733,18 +733,6 @@ void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
>  			info->severity, info->tlp_header_valid, &info->tlp);
>  }
>  
> -static void aer_print_port_info(struct pci_dev *dev, struct aer_err_info *info)
> -{
> -	u8 bus = info->id >> 8;
> -	u8 devfn = info->id & 0xff;
> -
> -	pci_info(dev, "%s%s error message received from %04x:%02x:%02x.%d\n",
> -		 info->multi_error_valid ? "Multiple " : "",
> -		 aer_error_severity_string[info->severity],
> -		 pci_domain_nr(dev->bus), bus, PCI_SLOT(devfn),
> -		 PCI_FUNC(devfn));
> -}
> -
>  #ifdef CONFIG_ACPI_APEI_PCIEAER
>  int cper_severity_to_aer(int cper_severity)
>  {
> @@ -1296,7 +1284,6 @@ static void aer_isr_one_error(struct aer_rpc *rpc,
>  			e_info.multi_error_valid = 1;
>  		else
>  			e_info.multi_error_valid = 0;
> -		aer_print_port_info(pdev, &e_info);
>  
>  		if (find_source_device(pdev, &e_info))
>  			aer_process_err_devices(&e_info);
> @@ -1315,8 +1302,6 @@ static void aer_isr_one_error(struct aer_rpc *rpc,
>  		else
>  			e_info.multi_error_valid = 0;
>  
> -		aer_print_port_info(pdev, &e_info);
> -
>  		if (find_source_device(pdev, &e_info))
>  			aer_process_err_devices(&e_info);
>  	}
> -- 
> 2.48.1.601.g30ceb7b040-goog
>